I haven't planned this to be a tutorial. More of a story of trying to make a boy happy. I didn't learn much, he didn't learn anything.
I wouldn't recommend forge and Minecraft to be a subject to learn coding from. It's bit well structured, it's but well explained, a lot of materials are not up to date, code is not documented, most tutorials don't even explain the versions of tools being used.
It's a great pity.